EXPERIMENTAL PROOF OF THE EXISTENCE OF THE “HALF-UNIT” 7-AMINO-4-METHYL-5-AZA-3-HEPTENE-2-ONE (AEH). CRYSTAL STRUCTURE OF A NOVEL DIBROMO-BRIDGED DICOPPER(II) COMPLEX (CuAEBr)₂

Abstract

Under suitable conditions, the single condensation of acetylacetone with ethylenediamine may occur to yield a “half-unit”, 7-amino-4-methyl-5-aza3-heptene-2-one (AEH), which has been characterized by ¹H and ¹³C NMR. The existence of this ligand is definitively supported by a single-crystal X-ray structural analysis of di-μ-bromo-bis(7-amino-4-methyl-5-aza-3-heptene-2-onato)(1-)dicopper(II). EPR spectra give proof of spin-spin interactions between pairs of copper ions within dimers in the solid state and in solution. Low temperature spectra suggest that the interaction is antiferromagnetic.